Pressure-driven metered mixing dispensing pumps and methods

ABSTRACT

A pressure-driven metered mixing dispensing pump has a first chamber, a second chamber, a third chamber in fluid communication with the first and second chambers and a fluid outlet in fluid communication with the third chamber. Selectively supplying a first fluid into the first chamber causes at least a portion of the first fluid and at least a portion of second fluid supplied into the second chamber to be mixed in the third chamber and dispensed through the fluid outlet.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a divisional application of U.S. patent applicationSer. No. 16/019,671, filed Jun. 27, 2018, now allowed, which is adivisional application of U.S. patent application Ser. No. 15/687,797,filed Aug. 28, 2017, now U.S. Pat. No. 10,066,611, issued Sep. 4, 2018,which is a continuation of U.S. patent application Ser. No. 14/302,529,filed Jun. 12, 2014, now U.S. Pat. No. 9,790,935, issued Oct. 17, 2017,all of which are incorporated herein by reference in their entirety.

FIELD OF THE DISCLOSURE

This disclosure relates generally to dispensing pumps, and, moreparticularly, to pressure-driven metered mixing dispensing pumps andmethods.

BACKGROUND

Some traditional appliances, such as a clothes washer, a clothes dryer,a clothes refresher, a non-aqueous clothes system, a dishwasher, etc.have dispensers for dispensing treating chemistry into a chamber inwhich items are placed for treatment. Other appliances, such as arefrigerator, a home carbonation device, a soda fountain machine, etc.may also have dispensers for dispensing other liquids such as aflavoring, etc.

SUMMARY

In one aspect, a pressure-driven metered mixing dispensing pump has afirst chamber, a second chamber, a third chamber in fluid communicationwith the first and second chambers and a fluid outlet in fluidcommunication with the third chamber. Selectively supplying a firstfluid into the first chamber causes at least a portion of the firstfluid and at least a portion of second fluid supplied into the secondchamber to be mixed in the third chamber and dispensed through the fluidoutlet.

In another aspect, a pressure-driven metered mixing dispensing pumpincludes a housing and a piston disposed in the housing, a first chamberwithin the housing, a second chamber within the housing, a third chamberwithin the housing and in fluid communication with the first and secondchambers, and a fluid outlet in fluid communication with the thirdchamber. Selectively supplying a first fluid into the first chambercauses at least a portion of the first fluid and at least a portion of asecond fluid supplied into the second chamber to be mixed in the thirdchamber and dispensed through the fluid outlet.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of an example appliance in the form of alaundry treating appliance having a pressure-driven metered mixingdispensing pump constructed in accordance with the teachings of thisdisclosure.

FIG. 2 is a schematic of an example control system for the laundrytreating appliance of FIG. 1.

FIG. 3 is a cross-sectional view of an example manner of implementingthe pressure-driven metered mixing dispensing pump of FIG. 1.

FIG. 4 is an exploded cross-sectional view of the pressure-drivenmetered mixing dispensing pump of FIG. 3.

FIGS. 5-7 are cross-sectional views showing example operations of thepressure-driven metered mixing dispensing pump of FIG. 3.

FIGS. 8 and 9 are cross-sectional views of alternative example mannersof implementing the pressure-driven metered mixing dispensing pump ofFIG. 1.

DETAILED DESCRIPTION

Traditional dispensing pumps for appliances use electrically drivenpumps that may be cost prohibitive and/or may require sophisticated pumpdrive control. Example pressure-driven metered mixing dispensing pumpsdisclosed herein are enhanced positive displacement pumps driven bywater pressure. The disclosed pumps are capable of dispensing accurateamounts of, for example, liquid treating chemistry mixed with water atselectively different and/or variable concentrations. Because thesebenefits are achieved via water valve control and eliminate the need foran electric metering pump substantial cost savings can be achieved usingthe disclosed example pumps. Further, because mixing and/or dilution canoccur within the disclosed pumps eliminating imprecise and/or costlyexternal mixing and/or dilution. Moreover, because the example pumpsdisclosed herein use negative pressure to draw treating chemistry intothe pumps, there is more flexibility in locating a reservoir containingthe treating chemistry within an appliance. Many conventional dispensersrely on gravity to move treating chemistry, and thus reservoirs must belocated up high in the appliance.

FIG. 1 is a schematic view of an example laundry treating appliance. Thelaundry treating appliance may be any appliance that performs a cycle ofoperation to clean or otherwise treat items placed therein, non-limitingexamples of which include a horizontal or vertical axis clothes washer;a combination washing machine and dryer; a tumbling or stationaryrefreshing/revitalizing machine; an extractor; a non-aqueous washingapparatus; and a revitalizing machine. Moreover, while the examplesdisclosed herein are described with reference to laundry appliances, itshould be understood that the example pressure-driven metered dispensingpumps disclosed herein may be a part of and/or be used in associationwith any number and/or type(s) of other appliances and/or devices suchas, but not limited to, a dishwasher, a refrigerator, a soda fountainmachine, a home carbonation drink machine, etc. Further still, while theexamples disclosed herein are described with reference to the meteringof treating chemistry and the mixing of treating chemistry with water,it should be recognized that the disclosed pumps may be used to meterand/or mix other types of fluids such as, but not limited to, liquids,gels, etc.

The laundry treating appliance of FIG. 1 is illustrated as ahorizontal-axis washing machine 10, which may include a structuralsupport system comprising a cabinet 12 that defines a housing withinwhich a laundry holding system resides. The cabinet 12 may be a housinghaving a chassis and/or a frame defining an interior that enclosescomponents typically found in a conventional washing machine, such asmotors, pumps, fluid lines, controls, sensors, transducers, and thelike.

The laundry holding system comprises a tub 14 supported within thecabinet 12 by a suitable suspension system and a drum 16 provided withinthe tub 14, the drum 16 defining at least a portion of a laundrytreating chamber 18. The drum 16 may include a plurality of perforations20 such that liquid may flow between the tub 14 and the drum 16 throughthe perforations 20. A plurality of baffles 22 may be disposed on aninner surface of the drum 16 to lift the laundry load received in thetreating chamber 18 while the drum 16 rotates. It is also within thescope of this disclosure for the laundry holding system to comprise onlya tub with the tub defining the laundry treating chamber.

The laundry holding system may further include a door 24 that may bemovably mounted to the cabinet 12 to selectively close both the tub 14and the drum 16. A bellows 26 may couple an open face of the tub 14 withthe cabinet 12, with the door 24 sealing against the bellows 26 when thedoor 24 closes the tub 14.

The washing machine 10 may further include a suspension system 28 fordynamically suspending the laundry holding system within the structuralsupport system.

The washing machine 10 may also include at least one ball balancing ring38 containing a balancing material moveable within the ball balancingring 38 to counterbalance an imbalance that may be caused by laundry inthe treating chamber 18 during rotation of the drum 16. The balancingmaterial may be in the form of metal balls, fluid or a combinationthereof. For example, the ball balancing ring 38 may comprises aplurality of metal balls suspended in a substantially viscous fluid. Theball balancing ring 38 may extend circumferentially around a peripheryof the drum 16 and may be located at any desired location along an axisof rotation of the drum 16. When multiple ball balancing rings 38 arepresent, they may be equally spaced along the axis of rotation of thedrum 16.

The washing machine 10 may further include a liquid supply system forsupplying water to the washing machine 10 for use in treating laundryduring a cycle of operation. The liquid supply system may include asource of water, such as a household water supply 40, which may includeseparate valves 42 and 44 for controlling the flow of hot and coldwater, respectively. Water may be supplied through an inlet conduit 46directly to the tub 14 by controlling first and second divertermechanisms 48 and 50, respectively. The diverter mechanisms 48, 50 maybe a diverter valve having two outlets such that the diverter mechanisms48, 50 may selectively direct a flow of liquid to one or both of twoflow paths. Water from the household water supply 40 may flow throughthe inlet conduit 46 to the first diverter mechanism 48, which maydirect the flow of liquid to a supply conduit 52. The second divertermechanism 50 on the supply conduit 52 may direct the flow of liquid to atub outlet conduit 54, which may be provided with a spray nozzle 56configured to spray the flow of liquid into the tub 14. In this manner,water from the household water supply 40 may be supplied directly to thetub 14.

The washing machine 10 may also be provided with a dispensing system fordispensing treating chemistry to the treating chamber 18 for use intreating the laundry according to a cycle of operation. The dispensingsystem may include a dispenser 62, which may be a single use dispenser,a bulk dispenser or a combination of a single and bulk dispenser.Non-limiting examples of suitable dispensers are disclosed in U.S. Pat.No. 8,196,441 to Hendrickson et al., filed Jul. 1, 2008, entitled“Household Cleaning Appliance with a Dispensing System Operable Betweena Single Use Dispensing System and a Bulk Dispensing System,” U.S. Pat.No. 8,388,695 to Hendrickson et al., filed Jul. 1, 2008, entitled“Apparatus and Method for Controlling Laundering Cycle by Sensing WashAid Concentration,” U.S. Pat. No. 8,397,328 to Hendrickson et al., filedJul. 1, 2008, entitled “Apparatus and Method for ControllingConcentration of Wash Aid in Wash Liquid,” U.S. Pub. No. 2010/0000581 toDoyle et al., filed Jul. 1, 2008, now U.S. Pat. No. 8,813,526, issuedAug. 26, 2014, entitled “Water Flow Paths in a Household CleaningAppliance with Single Use and Bulk Dispensing,” U.S. Pub. No.2010/0000264 to Luckman et al., filed Jul. 1, 2008, entitled “Method forConverting a Household Cleaning Appliance with a Non-Bulk DispensingSystem to a Household Cleaning Appliance with a Bulk Dispensing System,”U.S. Pat. No. 8,397,544 to Hendrickson, filed Jun. 23, 2009, entitled“Household Cleaning Appliance with a Single Water Flow Path for BothNon-Bulk and Bulk Dispensing,” and application U.S. Pat. No. 8,438,881,filed Apr. 25, 2011, entitled “Method and Apparatus for DispensingTreating Chemistry in a Laundry Treating Appliance,” which are hereinincorporated by reference in full.

Regardless of the type of dispenser used, the dispenser 62 may beconfigured to dispense a treating chemistry directly to the tub 14 ormixed with water from the liquid supply system through a dispensingoutlet conduit 64. To meter treating chemistry, and/or to mix a metereddose of treating chemistry with water, the example dispenser 62 includesa pressure-driven metered mixing dispensing pump 63 constructed inaccordance with the teachings of this disclosure. As described in detailbelow the example pressure-driven metered mixing dispensing pump 63 ofFIG. 1 meters an amount of treating chemistry and mixes the treatingchemistry with water in response to the selective supplying of water tothe pump 63 by selectively controlling a water valve (e.g., water valve335 of FIG. 3). The dispensing outlet conduit 64 may include adispensing nozzle 66 configured to dispense the treating chemistry intothe tub 14 in a desired pattern and under a desired amount of pressure.For example, the dispensing nozzle 66 may be configured to dispense aflow or stream of treating chemistry into the tub 14 by gravity, i.e. anon-pressurized stream. Water may be supplied to the dispenser 62 fromthe supply conduit 52 by directing the diverter mechanism 50 to directthe flow of water to a dispensing supply conduit 68.

Non-limiting examples of treating chemistries that may be dispensed bythe dispensing system during a cycle of operation include one or more ofthe following: water, enzymes, fragrances, stiffness/sizing agents,wrinkle releasers/reducers, softeners, antistatic or electrostaticagents, stain repellants, water repellants, energy reduction/extractionaids, antibacterial agents, medicinal agents, vitamins, moisturizers,shrinkage inhibitors, surfactants, color fidelity agents, andcombinations thereof.

The washing machine 10 may also include a recirculation and drain systemfor recirculating liquid within the laundry holding system and drainingliquid from the washing machine 10. Liquid supplied to the tub 14through tub outlet conduit 54 and/or the dispensing supply conduit 68typically enters a space between the tub 14 and the drum 16 and may flowby gravity to a sump 70 formed in part by a lower portion of the tub 14.The sump 70 may also be formed by a sump conduit 72 that may fluidlycouple the lower portion of the tub 14 to a pump 74. The pump 74 maydirect liquid to a drain conduit 76, which may drain the liquid from thewashing machine 10, or to a recirculation conduit 78, which mayterminate at a recirculation inlet 80. The recirculation inlet 80 maydirect the liquid from the recirculation conduit 78 into the drum 16.The recirculation inlet 80 may introduce the liquid into the drum 16 inany suitable manner, such as by spraying, dripping, or providing asteady flow of liquid. In this manner, liquid provided to the tub 14,with or without treating chemistry may be recirculated into the treatingchamber 18 for treating the laundry within.

The liquid supply and/or recirculation and drain system may be providedwith a heating system that may include one or more devices for heatinglaundry and/or liquid supplied to the tub 14, such as a steam generator82 and/or a sump heater 84. Liquid from the household water supply 40may be provided to the steam generator 82 through the inlet conduit 46by controlling the first diverter mechanism 48 to direct the flow ofliquid to a steam supply conduit 86. Steam generated by the steamgenerator 82 may be supplied to the tub 14 through a steam outletconduit 87. The steam generator 82 may be any suitable type of steamgenerator such as a flow through steam generator or a tank-type steamgenerator. Alternatively, the sump heater 84 may be used to generatesteam in place of or in addition to the steam generator 82. In additionor alternatively to generating steam, the steam generator 82 and/or sumpheater 84 may be used to heat the laundry and/or liquid within the tub14 as part of a cycle of operation.

Additionally, the liquid supply and recirculation and drain system maydiffer from the configuration shown in FIG. 1, such as by inclusion ofother valves, conduits, treating chemistry dispensers, sensors, such aswater level sensors and temperature sensors, and the like, to controlthe flow of liquid through the washing machine 10 and for theintroduction of more than one type of treating chemistry.

The washing machine 10 also includes a drive system for rotating thedrum 16 within the tub 14. The drive system may include a motor 88,which may be directly coupled with the drum 16 through a drive shaft 90to rotate the drum 14 about a rotational axis during a cycle ofoperation. The motor 88 may be a brushless permanent magnet (BPM) motorhaving a stator 92 and a rotor 94. Alternately, the motor 88 may becoupled to the drum 16 through a belt and a drive shaft to rotate thedrum 16, as is known in the art. Other motors, such as an inductionmotor or a permanent split capacitor (PSC) motor, may also be used. Themotor 88 may rotate the drum 16 at various speeds in either rotationaldirection.

The washing machine 10 also includes a control system for controllingthe operation of the washing machine 10 to implement one or more cyclesof operation. The control system may include a controller 96 locatedwithin the cabinet 12 and a user interface 98 that is operably coupledwith the controller 96. The user interface 98 may include one or moreknobs, dials, switches, displays, touch screens and the like forcommunicating with the user, such as to receive input and provideoutput. The user may enter different types of information including,without limitation, cycle selection and cycle parameters, such as cycleoptions.

The controller 96 may include the machine controller and any additionalcontrollers provided for controlling any of the components of thewashing machine 10. For example, the controller 96 may include themachine controller and a motor controller. Many known types ofcontrollers may be used for the controller 96. The specific type ofcontroller is not germane to this disclosure. It is contemplated thatthe controller is a microprocessor-based controller that implementscontrol software and sends/receives one or more electrical signalsto/from each of the various working components to affect the controlsoftware. As an example, proportional control (P), proportional integralcontrol (PI), and proportional derivative control (PD), or a combinationthereof, a proportional integral derivative control (PID control), maybe used to control the various components.

As illustrated in FIG. 2, the controller 96 may be provided with amemory 100 and a central processing unit (CPU) 102. The memory 100 maybe used for storing the control software that is executed by the CPU 102in completing a cycle of operation using the washing machine 10 and anyadditional software. Examples, without limitation, of cycles ofoperation include: wash, heavy duty wash, delicate wash, quick wash,pre-wash, refresh, rinse only, and timed wash. The memory 100 may alsobe used to store information, such as a database or table, and to storedata received from one or more components of the washing machine 10 thatmay be communicably coupled with the controller 96. For example, thememory 100 may be used to store a plurality of drum acceleration rampprofiles for respective ones of a plurality of ball balancing ring fluidviscosities. The database or table may also be used to store the variousoperating parameters for the one or more cycles of operation, includingfactory default values for the operating parameters and any adjustmentsto them by the control system or by user input.

The controller 96 may be operably coupled with one or more components ofthe washing machine 10 for communicating with and controlling theoperation of the component to complete a cycle of operation. Forexample, the controller 96 may be operably coupled with the motor 88,the pump 74, the dispenser 62, the pressure-driven metered mixingdispensing pump 63, a water valve 63A associated with thepressure-driven metered mixing dispensing pump 63, the steam generator82 and the sump heater 84 to control the operation of these and othercomponents to implement one or more of the cycles of operation.

The controller 96 may also be coupled with one or more sensors 104provided in one or more of the systems of the washing machine 10 toreceive input from the sensors, which are known in the art and not shownfor simplicity. Non-limiting examples of sensors 104 that may becommunicably coupled with the controller 96 include: a treating chambertemperature sensor, a moisture sensor, a weight sensor, a chemicalsensor, a position sensor, a load position sensor, a ball balancing ringball position sensor, a motor temperature sensor, and a motor torquesensor, which may be used to determine a variety of system and laundrycharacteristics, such as ball balancing ring 38 temperature, ballbalancing ring ball position(s), load position and/or laundry loadinertia or mass.

The washing machine 10 may have one or more pairs of feet 108 extendingfrom the cabinet 12 and supporting the cabinet 12 on the floor.

FIG. 3 is a cross-sectional side view of an example pressure-drivenmetered mixing dispensing pump 300 that may be used to implement theexample dispensing pump 63 of FIG. 1. FIG. 4 is an explodedcross-sectional view of the example pump 300 of FIG. 3. As shown and asdescribed in detail below, the example pump 300 of FIGS. 3 and 4 is anenhanced positive displacement pump that allows two fluids to be mixedwithin the pump 300. FIGS. 5-8 illustrate example operations of theexample pump 300 of FIGS. 3 and 4.

As used herein, terms such as left, right, top, bottom, end, etc. arewith reference to the orientation of the pump 300 shown in FIGS. 3 and4. If the pump 300 is considered with respect to another orientation, itshould be understood that such terms need to be correspondinglymodified.

The example pump 300 of FIG. 3 includes a housing 305 in which a piston310 is disposed. The piston 310 moves left and right within the housing305, as shown in FIGS. 5-7. The piston 310 and the housing 305 at leastpartially define first, second and third chambers 315, 316 and 317. Inthe example of FIGS. 3 and 4, seals 318 and 319 between the housing 305and the piston 310 at least partially fluidly isolate the chambers315-317 from each other. In some examples, the seals 318, 319 aredesigned and/or selected to leak respective fluids around the piston 310under temporary high line pressure conditions.

On the left end of the housing 305, the pump 300 includes a cap 320 thatmay, for example, be friction welded to the housing 305. On the rightend of the housing 305, the pump 300 includes another cap 325 that mayalso be friction welded to the housing 305. Additionally and/oralternatively, either or both of the caps 320, 325 may be attached oraffixed to the housing 305 via other means such as, for example, seals,clips, screws, adhesive, etc., and/or may be integral parts of thehousing 305.

In the example of FIG. 3, a water inlet 321 is defined in the left cap320 into which a push-to-connect tube fitting 322 is positioned. Thefitting 322 is configured to enable a plastic tube 330 to connect thepump 300 to a water supply valve 335. As described below in more detail,the controller 96 of FIGS. 1 and 2, and/or any other controller, canoperate the example pump 300 by controlling the water valve 335 toselectively supply water to the pump 300.

To allow the example pump 300 to work under different water pressures,the example water inlet 321 includes a flow control device 340 such as aflow control washer. The flow control device 340 protects the pump 300from high water pressure conditions. In some examples, the water inlet321 may further include a one-way valve 805 (see FIG. 8) that providesresistance to negative water line pressures.

In the example of FIG. 3, a treating chemistry inlet 326 is defined inthe right cap 325 into which a push-to-connect tube fitting 327 ispositioned. The fitting 327 is configured to enable a plastic tube 345to connect the pump 300 to a treating chemistry reservoir, container,pod, cartridge, or supply 350.

To control the flow of treating chemistry from the reservoir 350 intothe second chamber 316, the pump 300 includes a one-way valve 355. Inthe example of FIG. 3, the one-way valve 355 is a duck-bill valve.However, any other type of one-way valve may be used instead. Forexample, as shown in the alternative manner of implementing the pump 63of FIG. 1 shown in FIG. 9, the one-way valve 355 may be an umbrellacheck valve 905.

To control the flow of treating chemistry from the second chamber 316into the third chamber 317, the pump 300 includes another one-way valve360. In the illustrated example, the one-way valve 360 is held in placeby a retainer 361. In the example of FIG. 3, the one-way valve 360 is aduck-bill valve. However, any other type of one-way valve may be usedinstead. Moreover, other means of retaining the one-way valve 360 in thepiston 310 may be used. In the illustrated example, the outlet of theone-way valve 360 is located within the piston 310, and a portion of theinterior of the piston 310 is in fluid communication with the chamber317. In other words, a portion of the third chamber 317 is disposedwithin the piston 310. Compared to conventional positive displacementpumps, the placement of the one-way valve 360 within the piston 310simplifies the flow of the treating chemistry, thereby reducing pressurelosses due to viscosity and/or allowing higher viscosity treatingchemistry to be metered.

In some examples, the one-way valve 360 is modified and/or used togetherwith a modified retainer 361 having one or more orifices or smallpassages defined therethrough to provide a momentary or temporary higherpressure or shear force being applied to treating chemistry within thesecond chamber 316 to, for example, disintegrate the membrane enclosingvesicles of the treating chemistry.

To allow fluid to escape the third chamber 317, the example pump 300 ofFIG. 3 includes a fluid outlet 365 defined in the housing 305 into whicha push-to-connect tube fitting 366 is positioned. The fitting 366 isconfigured to enable a plastic tube (not shown) to directly orindirectly carry water, treating chemistry and/or a mixture of treatingchemistry and water from the pump 300 to, among other possible places,the dispensing nozzle 66 and the tub 14 (FIG. 1).

While push-to-connect tube fittings 322, 327, 366 and plastic tubing330, 340 are shown in FIG. 3, it should be understood that other typesof connectors (e.g., compression fittings, etc.) and/or types of fluidlines may be used.

To apply a leftward force to the piston 310, the pump 300 includes aspring 370. As the piston 310 moves rightward in response to water ofsufficient pressure (e.g., 20 to 120 pounds per square inch (PSI))entering the first chamber 315 via the inlet 321, the spring 370compresses and becomes loaded (see FIGS. 5 and 6). When the water valve335 is closed and water exits from the first chamber 315, the spring 370exerts a leftward force that returns the piston 310 to its leftwardposition.

In the illustrated example, the first chamber 315 has a larger diameterthan the second chamber 316 by a ratio of approximately 2:1. With such aratio, the thrust force caused by water pressure on the piston 310 underexpected water pressures (e.g., 20 to 120 PSI) is sufficient to overcomethe leftward force exerted by the spring 370 when fully loaded, pistonfriction forces, and the leftward force exerted on the piston 310 bytreating chemistry in the second chamber 316. Of course, other ratiosmay be selected for other operating conditions and/or applications.

To allow water to escape the first chamber 315 as the piston 310 ispushed leftward by the spring 370, the example piston 310 of FIG. 3includes one or more orifices, one of which is designated at referencenumeral 375. Water passing through the orifice 375 into the thirdchamber 317 mixes with treating chemistry entering the third chamber 317via the one-way valve 360 and the mixture is discharged from the thirdchamber 317 through the outlet 365, and/or the entering water washesand/or rinses treating chemistry remaining in or on the walls of thethird chamber 317 out through the outlet 365. The example orifice 375has a position, a shape and/or dimension(s) that bleeds water at apredetermined rate selected based on force(s) expected to be exerted onthe piston 310, expected and/or anticipated concentration(s) of treatingchemistry, a desired amount of mixing of the treating chemistry andwater, etc. In some example, the orifice 375 is shaped to act as a spraynozzle to improve mixing and/or removal of the treating chemistry fromthe third chamber 317. In some examples, the orifice 375 has a diameterof 1.5 millimeters (mm), and the pump 300 discharges a mixture of 4milliliters (mL) of treating chemistry and 100 mL of water per cycle ofthe pump 300.

Use of the orifice 375 provides numerous advantages that aren't possiblewith a conventional positive displacement pump. For example, precisemixing occurs within the third chamber 317 of the example pump 300(conventional positive displacement pumps can only dischargeconcentrated treating chemistry and rely on sometimes imprecise and/orcostly external mixing and/or dilution), there is no need to bleed offwater from the first chamber 315 via another valve, a separate externalline or other means, the water bled into the first chamber 315 reducestreating chemistry buildup within the third chamber 317, etc.

It should be understood that there may be more than one orifice, andthat the orifices need not have the same relative position, shape and/ordimension(s). In some examples, the seal 318 is configured to provide adesired bleeding flow rate similar to the orifice 375, and the orifice375 is omitted. In such examples, the seal 318 could alternatively be adiaphragm-type of seal having the desired bleeding flow rate. In stillother examples, the orifice 375 is replaced by an orifice, an internalflow line, and/or an external flow line that bypasses the piston 310. Inyet more examples, the orifice 375 is replaced by any other means tobleed water such as, but not limited to, a needle valve.

It is also contemplated that in other examples that all or some of thewater in the first chamber 315 is not bled into the third chamber 317.For example, all of the water could be bled externally from the firstchamber 315 into the tub 14 (i.e., into the treating chamber of thelaundry appliance 10) where, for example, it is used as part of atreating cycle of operation. In such an example, the pump 300 dischargesconcentrated treating chemistry. After use in the treating cycle ofoperation, the bled water would be discharged from the tub 14 via thepump 74. In other examples, a water flow device (e.g., a three-wayvalve) is selectively controlled to (a) bleed water from the firstchamber 315 into the third chamber 317 so the pump 300 discharges mixedor diluted treating chemistry, or (b) bleed water from the first chamber315 into the tub 14 so the pump 300 discharges concentrated treatingchemistry. In such examples, the water flow device could be controlledso that a portion of the water in the first chamber 315 is bled into thetub 14, and the remainder is bled into the third chamber 317. Via anycombination of these examples, variable dilution of treating chemistrycan be selectively obtained using the disclosed example pump 300.

Turning to FIGS. 5-7, example cycle of operation of the example pump 300of FIGS. 3 and 4 are shown. As shown in FIG. 5, as a first fluid (e.g.,water) of sufficient pressure enters first chamber 315 via the inlet321, the piston 310 begins to move rightward.

As shown in FIG. 6, as the first fluid continues to enter the chamber315, the piston 310 continues moving rightward, the volume of the firstchamber 315 increases, and the volume of the second chamber 316decreases. As the volume of the second chamber 316 decreases thepressure of second fluid 605 (e.g., a treating chemistry) present in thesecond chamber 316 increases and, thus, passes, flows and/or is ejectedthrough the one-way valve 360 into the third chamber 317. As the secondfluid 605 is being ejected into the third chamber 317, first fluid 610passes through the orifice 375 into the third chamber 317 and mixes withthe second fluid 605. The mixture of the first and second fluids 605,610 is discharged through the outlet 365.

As shown in FIG. 7, when the flow of first fluid into the first chamber315 is stopped or discontinued, the spring 370 moves the piston 310leftward thereby decreasing the volume of the first chamber 315, andincreasing the volume of the second chamber 316. As the volume of thefirst chamber 315 decreases the first fluid 610 continues to passthrough the orifice 375 into the third chamber 317. As the first fluid610 continues to pass into the third chamber 317 any second fluid 605 inthe third chamber 317 is diluted, rinsed and/or washed out of the pump300 through the outlet 365. As the volume of the second chamber 316increases, a negative pressure is created inside the second chamber 316thereby drawing second fluid into the second chamber 316 via the one-wayvalve 355.

It should be understood that the amount of the second fluid that isdischarged, the amount of the first fluid mixed with the second fluid,and/or the amount of the first fluid used to remove remaining secondfluid from the third chamber 317 during each cycle of operation of thepump 300 can be selectively, adaptively and/or dynamically controlled.For example, a larger amount of the first fluid can be used to removesecond fluid from the third chamber 317 by holding the position shown inFIG. 6 for a longer period time. Because the full volume of the secondchamber 316 is known, precise amounts of the second fluid can bedispensed. An example second chamber 316 is capable of holding 4 mL ofsecond fluid and, thus, a full stroke of the pump 300 would dispenseprecisely 4 mL. However, different amounts of the second fluid can bedispensed using a sensor to sense the position of the piston 310 and/orby shortening the amount of time that the first fluid is allowed toenter the first chamber 315. Moreover, additional amounts of the secondfluid can be discharged by cycling the pump 300 multiple times. Furtherstill, the water line pressure applied to the pump 300 may beselectively and/or dynamically manipulated to maintain the position ofthe piston 310 such that the chamber 317 is as large as desired and/orreasonably feasible, thereby allowing the chamber 317 to the rinsed foran extended period of time. Thus, it will be understood that the examplepumps disclosed herein can be adaptively, selectively, and dynamicallycontrolled to dispense any amount of the second fluid mixed with anyamount of the first fluid.

FIGS. 8 and 9 illustrate alternative manners of implementing the examplepump 63 of FIG. 1. For clarity, only those reference numerals needed toillustrate differences from FIGS. 3 and 4 will be shown in FIGS. 8 and9. In the illustrated example of FIG. 8, the inlet 321 includes the flowcontrol device 340 and the one-way valve 805. In the illustrated exampleof FIG. 9, the duck-bill valve 355 of FIG. 3 is replaced with anumbrella check valve 905. Of course others of the one-way valves 360,805 may be replaced with the same and/or different type(s) of one-wayvalves.

Although certain example methods, apparatus and articles of manufacturehave been described herein, the scope of coverage of this patent is notlimited thereto. On the contrary, this patent covers all methods,apparatus and articles of manufacture fairly falling within the scope ofthe claims of this patent.

What is claimed is:
 1. A pressure-driven metered mixing dispensing pump,comprising: a first chamber; a second chamber; a third chamber in fluidcommunication with the first and second chambers; and a fluid outlet influid communication with the third chamber, wherein selectivelysupplying a first fluid into the first chamber causes at least a portionof the first fluid and at least a portion of second fluid supplied intothe second chamber to be mixed in the third chamber and dispensedthrough the fluid outlet.
 2. A pressure-driven metered mixing dispensingpump as defined in claim 1, further comprising a piston having a firstorifice defined therethrough, and wherein the first and third chambersare in fluid communication via the first orifice.
 3. A pressure-drivenmetered mixing dispensing pump of claim 2, wherein the first orifice isconfigured to spray the at least a portion of the first fluid into thethird chamber.
 4. A pressure-driven metered mixing dispensing pump ofclaim 2, wherein the piston has a second orifice defined therethrough,and the first and third chambers are in fluid communication via thefirst and second orifices.
 5. A pressure-driven metered mixingdispensing pump of claim 1, further comprising at least one of aninternal bypass line, an external bypass line, a water piston sealand/or a diaphragm-type seal having a non-zero predetermined bleedingflow rate, wherein the first and third chambers are in fluidcommunication via the at least one of the internal bypass line, theexternal bypass line, the water piston seal, and/or the diaphragm-typeseal.
 6. A pressure-driven metered mixing dispensing pump of claim 1,wherein the selective supplying of the first fluid from a first fluidsource into the first chamber causes substantially all of the secondfluid in the third chamber to be removed from the third chamber.
 7. Thepressure-driven metered mixing dispensing pump of claim 1, furthercomprising a first one-way valve positioned between the second chamberand the third chamber.
 8. The pressure-driven metered mixing dispensingpump of claim 7, wherein the first one-way valve is disposed at leastpartially within the piston.
 9. The pressure-driven metered dispensingpump of claim 1, wherein the first fluid is supplied by a domestic watersource, and the second fluid comprises a laundry treating chemistry. 10.A pressure-driven metered mixing dispensing pump, comprising: a housingand a piston disposed in the housing; a first chamber within thehousing; a second chamber within the housing; a third chamber within thehousing and in fluid communication with the first and second chambers;and a fluid outlet in fluid communication with the third chamber,wherein selectively supplying a first fluid into the first chambercauses at least a portion of the first fluid and at least a portion of asecond fluid supplied into the second chamber to be mixed in the thirdchamber and dispensed through the fluid outlet.
 11. The pressure-drivenmetered mixing dispensing pump of claim 10, wherein the piston isselectively controllable to move between a first position and a secondposition.
 12. The pressure-driven metered mixing dispensing pump ofclaim 11, wherein the piston is in the first position when the firstfluid is selectively suppled into the first chamber.
 13. Thepressure-driven metered mixing dispensing pump of claim 12, wherein inthe first position, substantially none of a first fluid in the firstchamber is directed into the third chamber.
 14. The pressure-drivenmetered mixing dispensing pump of claim 13, wherein in the secondposition, a volume of the first chamber is expanded and substantiallyall of the first fluid in the first chamber is directed into the thirdchamber and a volume of the second chamber is contracted causing thesecond fluid from the second chamber to enter the third chamber and bemixed in the third chamber with the first fluid from the first chamber.15. The pressure-driven metered mixing dispensing pump of claim 10,wherein the piston has at least one orifice defined therethrough toeject the at least some of the first fluid from the first chamber intothe third chamber.
 16. The pressure-driven metered mixing dispensingpump of claim 10, further comprising at least one seal between thehousing and the piston to at least partially fluidly isolate the first,second and third from each other.
 17. The pressure-driven metered mixingdispensing pump of claim 16, wherein the at least one seal provides adesired bleeding flow rate between the first chamber and the thirdchamber.
 18. The pressure-driven metered mixing dispensing pump of claim10, further comprising a first one-way valve positioned between thesecond chamber and the third chamber.
 19. The pressure-driven meteredmixing dispensing pump of claim 10, wherein the first one-way valve isdisposed at least partially within the piston.
 20. The pressure-drivenmetered mixing dispensing pump as defined of claim 10, furthercomprising a spring configured to move the piston from the secondposition to the first position.